1. Field of the Invention
The present invention relates to a linear guide table system including a pair of linear guide apparatuses respectively having sliders which are movable linearly by being guided by guide rails, and including a common table fixed to upper surfaces of the sliders.
2. Description of the Prior Art
A prior art linear guide table system of this type is disclosed, for example, in Japanese Patent Publication No. 62-11208. The linear guide table system includes a pair of linear sliding bearings (linear guide apparatuses) and a table fixed to upper surfaces of sliders across the sliders. The slider has an inverted C-shaped cross section and has a recess opening downwardly. One side wall of the slider has an upward slant surface formed in an upper portion of an inner surface, and the other side wall of the slider has a downward slant surface formed in an inner surface. Load ball grooves extending in a longitudinal direction and having a semicircular cross section are respectively formed in the upward slant surface and in the downward slant surface, and no-load ball holes extending in the longitudinal direction are respectively formed in both side walls.
On the other hand a guide rail of each linear guide apparatus has a cross section of at least an upper portion substantially the same as the shape of the recess portion of the slider. The guide rail has a downward slant surface formed by cutting out one side surface in substantially an L shape, and a downward rolling groove having a semicircular cross section and extending in the longitudinal direction is formed in the downward slant surface. Furthermore, a shoulder portion of the other side of the guide rail is cut out to form an upward slant surface, and an upward rolling groove having a semicircular cross section and extending in the longitudinal direction is formed in the upward slant surface.
In this prior art system, the number of the load ball grooves of the slider, and the number of the ball rolling grooves of the guide rail of the linear guide apparatus can be reduced for each side from two to one. As a result, the working cost can be reduced.
However, in this prior art system, the upward slant surface and the downward slant surface are respectively formed in the inner side of the slider and in the outer side of the guide rail, and one load ball groove and one ball rolling groove are formed respectively in the upward and downward slant surfaces. As a result, the shapes of the cross sections of the slider and the guide rail are not in bilateral symmetry and are complicated. Thus, there is a problem in that it is impossible to additionally form the load ball groove and the ball rolling groove to increase the number of grooves to two grooves for each side thereby to enable to use for general purpose.